Abstract

We reconstruct the common envelope (CE) phase for the observed sample of white dwarf-main sequence post-common envelope binaries, with and without considering the internal energy of the progenitor giants' envelope. Using multi-regression analysis in the former case, we can model the CE ejection efficiency, αCE, in terms of the orbital period of the progenitor binary at the start of the CE phase. Considering the latter, αCE can be modelled in terms of the white dwarf mass. Finally, we compare our work with similar studies by Zorotovic et al. (2010) and De Marco et al. (2011).